Efficiency, Selectivity and Reusability of CuFe2O4 Nanoferrite Particles for Reductive Transformation of P-Nitrophenol to P-Aminophenol

Abstract

MFe2O4(Where M = Cu2+, Co2+and Ni2+) has been synthesized using a citrate sol-gel self-ignition process in order to investigate their catalytic performance for reduction of p-nitrophenol. The ignited precursors were annealed at 400, 600, 800 and 1000°C for 2 hrs. to obtain nanoferrite particles. The prepared samples were characterized using various instrumental techniques like FT-IR, XRD, and UV-VIS. X-ray analysis confirms the formation of single phase. Powder X-Ray diffraction patterns showed the formation of body centered tetragonal structure for CuFe2O4and cubic structure for CoFe2O4and NiFe2O4. It was observed that as the annealing temperature increases from 400 to 1000°C, the XRD peaks grow sharper attributing to an increase in particle size with increasing temperature; which is consistent with TEM. Transmission Electron micrographs analysis revealed an enhancement in grain size with the annealing temperature. The disappearance of yellow colour indicated the conversion of p-nitrophenol to p-aminophenol and the occurrence of colour disappearance has been observed in one minute using CuFe2O4(8mol %). This suggested the efficiency of CuFe2O4in catalyzing p-nitrophenol reduction. FT-IR and UV-Visible spectroscopy has been used to confirm this reduction process. FT-IR spectra showed N-H stretching vibrations at ~3365 cm-1and 3350 cm-1attributing to the formation of primary amine using CuFe2O4for catalyzing reduction of p-nitrophenol. The disappearance of the absorption band at 400 nm in the UV-Visible spectrum also confirms the conversion of p-nitrophenol to p-aminophenol.